Question

in an ap if Sn =4n-n2 then d is ​

Answer 1

Answer:

d = -2

Step-by-step explanation:

Because the sum of first n terms of any AP is in the form (d/2)n² + (a - d/2)n, where d is the common difference and a is the first term. So that the coefficient of n² is half of the common difference.

Here in S_n = 4n - n², the coefficient of n² is -1, so that half of common difference is -1. Therefore, common difference is -1 × 2 = -2.

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Answer 2

there is some problem with the question......... may be it must be Sn=4n^2-2n. then ans.